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What is the function of PCR? PCR produces exponentially large amounts of a specific piece of DNA from trace amounts of starting material. PCR produces exponentially large amounts of a specific piece of DNA from trace amounts of starting material.

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What you already know…. There are 23 pairs of chromosomes which contains 30,000 to 50,000 genes. There are 23 pairs of chromosomes which contains 30,000 to 50,000 genes. These genes only comprise about 5 % of chromosomal DNA. These genes only comprise about 5 % of chromosomal DNA. The other 95% is non-coding DNA. The other 95% is non-coding DNA. The sequence with the genes are introns, which is transcribed into RNA but in the end do not make a protein. The sequence with the genes are introns, which is transcribed into RNA but in the end do not make a protein.

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What you already know cont… The sequence that do code for proteins are called exons. The sequence that do code for proteins are called exons. Both introns and exons are initially transcribed, then introns are spliced out of the RNA to create the messenger RNA (mRNA). Both introns and exons are initially transcribed, then introns are spliced out of the RNA to create the messenger RNA (mRNA).

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About the exons and introns Exon sequences are similar among individuals. Exon sequences are similar among individuals. Introns vary in size and number among individuals. Introns vary in size and number among individuals. It is the difference in intron sequences that allows us to determine human genetic diversity. It is the difference in intron sequences that allows us to determine human genetic diversity.

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The Alu Sequence The Alu sequence is about 300 base pairs long that is repeated, one copy at a time, almost 500,000 times within the human genome. The Alu sequence is about 300 base pairs long that is repeated, one copy at a time, almost 500,000 times within the human genome. The origin and function of the Alu sequence is not yet known. The origin and function of the Alu sequence is not yet known.

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The Hardy-Weinberg equation p 2 + 2 pq + q 2 = 1 Where: p and q represents alleles. p 2 = the expected frequency of the homozygous (+/+) genotype in the population. p 2 = the expected frequency of the homozygous (+/+) genotype in the population. 2pq = the expected frequency of the heterozygous (+/-) genotype in the population. 2pq = the expected frequency of the heterozygous (+/-) genotype in the population. q 2 = the expected frequency of the homozygous (-/-) genotype in the population. q 2 = the expected frequency of the homozygous (-/-) genotype in the population.

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The Hardy-Weinberg equation This equation describes the frequencies of genotypes in a population that is at genetic equilibrium, meaning that the frequencies are stable from generation to generation. This equation describes the frequencies of genotypes in a population that is at genetic equilibrium, meaning that the frequencies are stable from generation to generation.

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The Hardy-Weinberg Theory The theory states that for a population to achieve this equilibrium, the population must be: The theory states that for a population to achieve this equilibrium, the population must be: Very largeVery large The members must mate randomly and produce offspring with equal successThe members must mate randomly and produce offspring with equal success there must be no migration of individuals into or out of the population.there must be no migration of individuals into or out of the population.